1. Field of the Invention
The present invention relates to a thermal printer and a portable terminal.
2. Description of the Related Art
Hitherto, a thermal printer has been known as a printer configured to perform printing on a recording sheet (heat-sensitive paper). The thermal printer includes a thermal head, a platen roller, and a frame. The thermal head includes a heating element. The platen roller is configured to feed the recording paper by nipping the recording paper with the thermal head. The frame is configured to support the platen roller and the thermal head. In the thermal printer, the heating element of the thermal head is caused to generate heat as appropriate during a course of feeding the recording paper through rotation of the platen roller, thereby being capable of printing various information on the recording paper.
The above-mentioned thermal head is supported on the frame so as to be turnable under a state of being fixed to a head support plate. An urging member configured to urge the thermal head against the platen roller is interposed between the frame and the head support plate. With this, the thermal head is pressed against an outer peripheral surface of the platen roller.
Incidentally, particularly for a thermal printer which is to be mounted to a portable terminal such as a card payment terminal, downsizing in a thickness direction, that is, in a direction in which the thermal head approaches and separates from the platen roller has been demanded. In order to downsize the thermal printer in the thickness direction, it is conceivable to reduce a space for a head back surface region, that is, a region between a back surface of the head support plate and the frame.
However, for a related-art thermal printer, there is a limit in downsizing the thermal printer in the thickness direction while securely pressing the thermal head against the platen roller. Therefore, for the thermal printer of this type, downsizing in the thickness direction has been demanded.